The Falcons defense has seen its share of highs and lows this season. Whether it was blasting the Buccaneers at home or laying an egg in Cincinnati, their defense has already run the gamut.

Which defense shows up will go a long way in deciding whether they’re up to slowing down a clicking Big Blue offense, or whether they’ll get run over like the Redskins a week and a half ago. The Falcons only have three sacks this season — and none by former Giants defensive end Osi Umenyiora.

If Umenyiora, who is playing out of position as an outside linebacker, can have a flashback and generate a pass rush, the Falcons may have a chance of neutralizing the improved Giants passing game.

“I think we are just very inconsistent,” Umenyiora told the New York media in a conference call Wednesday. “We play good one week and then the next week, we don’t play quite as well. We have to find a way to be more consistent in our play.”

2. In a tight spot

The passing game has been aided by stellar tight end play, as seven of quarterback Eli Manning’s nine touchdowns have been caught by either Larry Donnell (four) or backup Daniel Fells (three).

Atlanta has been riddled by both injuries to starting linebackers and miscasting players like Umenyiora and Kroy Biermann. Each were once meddlesome defensive ends in their prime, but have now been shifted to open space.

It’ll be intriguing to see how the Giants attack them in the passing game during the rare times they’re forced to cover a tight end or running back out of the backfield. Smart money says neither linebacker will be able to run with Donnell, Fells or the running backs.

3. Take the ball and run with it

Manning has used a revamped running game to boost his once-anemic passing numbers. During the Giants’ 0-2 start, they averaged just 134 yards rushing per game. But during their back-to-back wins, the running game has amassed 358 total yards.

Such an improved ground game expertly sets up the play-action passing game, which puts even more stress on a defense. If the Giants continue the trend of hammering out yards on the ground — much the way Rashad Jennings garnered a career-high 176 yards the last time they played at home — the Falcons’ front seven will be in for a long afternoon.

Jennings’s role as the feature back has been a pleasant surprise for anyone outside the facilities, but to the players and coaches, this is why they brought Jennings over from Oakland after two prior stints as an understudy.